Snowmobile design has incrementally moved towards more powerful motors, with a resulting increase in the weight of the machines due to the larger motor and corresponding support structure. Frequently, increased weight results in a higher center of gravity of the snowmobile. Increased weight and increased center of gravity can have a detrimental affect on the ride quality and handling characteristics of the snowmobile.
Handling, cornering and ride quality are largely dependent upon the front suspension system of the snowmobile. It is common practice to suspend the skis of a snowmobile independently by means of respective strut type suspensions. It is desirable to provide some form of stabilizer or sway bar arrangement interconnecting the front skis to reduce the amount of leaning that occurs during cornering of the snowmobile. Due to the rough and sometimes uncertain terrain over which snowmobiles are ridden, it is desirable that the stabilizer arrangement be positioned so that it will be protected if unexpected objects are encountered, such as disclosed in U.S. Pat. No. 4,690,234 (Takada).
U.S. Pat. No. 4,489,954 discloses an anti-roll mechanism that includes a torsion bar supported by the body that is connected to the skis for torsion loading upon independent movement of the skis relative to the body. The connection between each of the skis and the torsion bar is such that the torsion bar is loaded by the pivotal movement of the skis about their steering axes for providing a self-centering force on the skis.
U.S. Pat. No. 4,671,521 (Talbot, et al) discloses a snowmobile ski suspension including upper and lower transverse suspension arms vertically spaced and each having an outboard end articulated to a ski spindle and an inboard end articulated to a fixed mounting on the frame of the snowmobile. The upper and lower transverse suspension arms define a parallelogram linkage for guiding the spindle to move generally vertically with respect to the snowmobile.
U.S. Pat. No. 5,029,664 (Zuwalski) discloses a suspension system with a geometry that includes upper and lower suspension linkages of predetermined lengths in cooperation with a spindle of a predetermined length for eliminating lateral movement of the skis during suspension travel. The respective linkages and spindles are interconnected by ball joints at predetermined locations in such a manner that during deflection of the suspension system, a ski attached to the lower end of the spindle moves substantially in a line parallel to a vertical plane which contains the longitudinal axis of the snowmobile.
What is needed is a snowmobile design that provides a high power-to-weigh ratio while maintaining optimum handling characteristics and ride quality.